Reference for Zevachim 12:10

אי דאפרשינהו בבת אחת הכי נמי הכא במאי עסקינן דאפרשינהו בזה אחר זה

but that Scripture spared them.<span class="x" onmousemove="('comment',' For the strain and obligation would be too great.');">¹³</span> Now in this case it is a positive command [violated] after the separation [of the animals],<span class="x" onmousemove="('comment',' They were separated the previous day. The injunction against entering the Sanctuary lies in the passage: Command the children of Israel, that they put out of the camp . . whosoever is unclean by the dead (Num. V, 2) . Since this is expressed affirmatively, it ranks as a positive command.');">¹⁴</span>

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